Remove duplicate devDep.
Remove duplicate devDep.

SaladFork/ember-computed-decorators,martndemus/ember-computed-decorators,SaladFork/ember-computed-decorators,martndemus/ember-computed-decorators,rwjblue/ember-computed-decorators,rwjblue/ember-computed-decorators,rwjblue/ember-computed-decorators